Polish railway signalling


The Polish railway signalling system provides a complex outlook of traffic situations, yet is quite easy to understand. Signals can be divided into following categories:
Most signals are [|colour lights].
On few stations remained [|mechanical] signals, as well as [|old colour light signals].

Colour light signals

Semi-automatic signals

Semi-automatic is the most important type of signal on Polish railways. Its name reflects the fact that it switches to a red aspect automatically after a train has passed it but it must be switched back to clear by an explicit action from a signal box or dispatch centre. It is the typical signal in use at stations.
A [|semi-automatic] signal can be recognized by its post which is painted with red and white strips. Dwarf versions have their boxes painted so.
A red aspect on a semi-automatic signal must not be passed.
As presented on this compact chart, semi-automatic signals can display both near and distant functions. Near signals either command a stop or impose a certain speed limit beginning at that signal. Distant signals tell the driver what to expect at the next signal, especially when braking is required.

Other speeds

Since 2007 the Ie-1 code which regards signalling allows other speed limits. They are indicated by a number representing the speed in tens of km/h which is lit only with adequate aspect of the signal. These numbers are incorporated into signalling so, that they always loosen the restriction presented by the aspect of signal.
On distant signals and repeaters these other speeds are not displayed, therefore more restrictive aspect is effectively announced.

Nameplates

Semi-automatic signals on a station are tagged with consecutive letters of Latin alphabet, or with a letter followed by a number.
The nameplates also contain speed indication which appears as a superscript or a fraction. The numbers have following meaning:
Therefore, a nameplate H 1/2 means a signal named H that aside S1 will also display S2-S5 aspects for straight direction and S10-S13 for diverging direction. Whereas P3 2 means a signal of name P3 that aside S1 only displays S10-S13 aspects because it is only followed by diverging direction.
There may also be a letter m which specifies that this signal also functions as a shunting signal.

Subsidiary signal

Automatic signals

Automatic signals are used on lines equipped with automatic block signaling. Their colour language is the same as aspects S1-S5 of semi-automatic signals. The main difference regards the S1 aspect - After stopping, it can be passed but the subsequent maximum speed is limited to 20 km/h.
Automatic signals have their posts painted white to be easily distinguished from semi-automatic signals.

Distant-only signals

Distant-only signal is used on lines not equipped with ABS and lines with 2-state ABS. These signals are usually placed at braking distance from the next signal. The aspects they display are the same as signal aspects S2-S5, making them technically a signal which is just incapable of displaying a S1 aspect.
Their posts are painted grey and equipped with a distant-only signal sign.

Repeater signals

When a signal aspect is not visible from the proper distance, a repeater signal is installed to aid drivers. Up to three repeaters may be installed if needed. A repeater signal is not a substitute for a distant-only signal.
Their posts are painted grey and equipped with plates with Roman numerals: III, II, I where the "I" stands closest to the main signal. Their colour language is identical to warning shields, except the fact they also have a continuously glowing white light, which informs that this is not a main signal but a repeater.
The following table presents as an example, a station-entry signal designated "B" displaying the aspect S13 preceded with distant-only signal and three repeaters:

Level crossing warning

Level crossing warning is placed in a braking distance before an automatic level crossing. The signal tells the driver whether automobile drivers are warned about an approaching train. Normally, level crossing warning signals display no aspect. They light up in the front of an approaching train which is the first clue that the system is working correctly.
Level crossing warning signals are unrelated to other signals, therefore in case of Osp1 signal a train must proceed at 20 km/h regardless the higher speed allowed by last signal.
Their posts are painted black and white strips.

Shunting signals

signal is used exclusively at stations. A consist shunting on such signals must not leave the station. Shunting signals are either stand-alone or incorporated into semi-automatic signals, which bear letter "m" on such occasions.
Stand-alone shunting signals have their posts painted gray, except in the case it is a part of the semi-automatic signal, which is painted white-red stripes.

Old colour light signals

The colour light signals installed between 1959 and 1969 differ from the contemporary system. They are still in use on several stations. As a matter of fact they can also be used with ETCS Level 1, only the LEU unit must be reprogrammed to understand certain combinations of lights differently.

Mechanical signals